The estrogen-inducible RING finger protein Efp stimulates proliferation of breast cancer cells. 14-3-3 is p53-inducible protein that sequesters mitotic Cdks in the cytoplasm to inhibit entry into mitosis. To allow cell-cycle progression, estrogens stimulate production of Efp, which binds and ubiquinates 14-3-3s sigma. 14-3-3s marked with ubiquitin chains is recognized and destroyed by the proteosome. Released Cdks are now free to escape into the nucleus and promote mitotic entry.

Contributor: Kosi Gramatikoff, PhD

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